Propulsion

ARCAA is currently researching the development and integration of small hybrid propulsion systems for application on small UAVs. The research program investigates:

1. Development of Hybrid Propulsion Systems for UAS

Hybrid powerplants combining Internal Combustion Engine and Electric Motor prime movers have been extensively developed for land and marine based transport systems. This research investigates the development of a hybrid propulsion system for application on small UAVs.

Prototype hybrid powerplant fitted on the dynamometer.

The use of such powerplants in airbourne propulsion systems has been hitherto impractical due to energy and power density constraints in batteries and electric machines. Recent improvements in battery and electric motor technology have enabled advances in propulsion technology for some aircraft. In this work a prototype Aircraft Hybrid Powerplant was designed, constructed and tested. Analysis to determine the practical feasibility as well as improvements in UAV range and endurance is in progress. A custom designed dynamometer was manufactured and implemented in wind tunnel tests to measure prototype system performance. The prototype will be fitted to an ARCAA UAV for flight trials.

Schematic of hybrid propulsion system

Publications

• Hybrid Propulsion Publications (QUT ePrints)

Related Sites

Research Personnel

• Mr. Richard Glassock
• Dr. Felipe Gonzalez
• Prof. Rodney Walker

Related Media

	This picture shows the dynamometer fitted with a propeller wind turbine.
	This picture shows the prototype hybrid powerplant fitted on the dynamometer.   Click on the image for a video of the prototype Aircraft Hybrid Powerplant in operation.

1. Multi-objective Mission Planning for UAS with hybrid propulsion systems

Hybrid propulsion systems are being introduced onboard UAS with the main objective of reducing the fuel consumption. The process of mission planning should look to optimise the efficiencies offered by hybrid propulsion systems. However, such efficiencies may come at the expense of other factors important in the mission planning for UAS e.g. mission (time, distance) and payload efficiency, and airspace rules and weather.

Typical UAS mission profile requiring optimisal use of a hybrid propulsion system

This research investigates the development of a multi-objective mission planning system which optimises the use of hybrid propulsion systems onboard fixed wing UASs.

Current research can be divided into two sections:

• Modelling of hybrid powerplant onboard an UAS; and
• Multi-objective mission planning for UAS.

The first section focuses on the development of a simulation model of a hybrid powerplant onboard an UAS in the MATLAB® Simulink® simulation environment. 

The simulation model is capable of executing a specified flight mission inputted as a series of waypoints.  A typical mission scenario includes basic UAS operations such as Climb, Cruise, Descent and Loiter, such as shown in the following mission profile.  The Loiter phase enables specific tasks that require flying at a low altitude, such as video recording, to be carried out.

The second section focuses on investigating the use of evolutionary algorithms (EAs) in the area of multi-objective optimisation of a flight mission for UAS.  EAs have been proven successful in other areas of optimisation, such as aircraft design.

Although computationally more intensive than traditional gradient-based methods, preliminary results have shown that EAs are able to provide more optimised results than gradient-based methods.

Ultimately, the two sections will be combined to provide multi-objective mission planning capabilities for hybrid-powered UAS.

This research employs techniques drawn from the System Design and Optimization Research Theme.

Publications

• Multi-Objective Mission Planning for UAS with hybrid propulsion systems Publications on QUT ePrints

Related Sites

• System Design and Optimization Research Theme
• Multi-criteria mission planning

Research Personnel

• Ms. Jane Hung
• Dr. Felipe Gonzalez
• Prof. Rodney Walker

Related Media